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Numerical Simulation Of Electroosmotic Flow Of Viscoelastic Fluid In Microchannel, Jianyu Ji

Mechanical & Aerospace Engineering Theses & Dissertations

Electroosmotic flow (EOF) has been widely used in various biochemical microfluidic applications, many of which often involve the use of viscoelastic non-Newtonian fluids. Due to the existence of the elastic effect, the viscoelastic EOF develops into chaotic flow under extremely low Reynolds numbers, which is known as elastic turbulence. The mechanism of elastic turbulence in electroosmotic flow remains unclear. Numerical simulation plays an important role in understanding the mechanisms of elastic turbulence. This dissertation is aimed to study the EOF of viscoelastic fluids in constriction microchannels under various direct current (DC) and alternating current (AC) electric fields. First, the EOF …

A Systems Theory-Based Framework For Environmental Scanning In Complex System Governance, Dale E. Baugh

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research was to develop a Systems Theory-based framework for Environmental Scanning (ES) in Complex System Governance (CSG) using an inductive research design. Complexity and uncertainty are normal for external environments in which today’s systems (organizations) exist. These environmental characteristics provide impetus for researchers to focus on organizational planning for disruptive external forces that could threaten system stability and future system existence. The ES function supports the requisite governance metasystemic functions to be enabled, executed, and evolved sufficiently well to promote continuous system viability. In this research the functioning of ES was examined from a diverse literature-based …

Assembly Of Ceramic Particles In Aqueous Suspensions Induced By High-Frequency Ac Electric Field, James E. John Iv

Mechanical & Aerospace Engineering Theses & Dissertations

Ceramic materials processed using colloidal methods have been the focus of a great deal of research aimed at tailoring the final structure and microstructure of the finished ceramic sample. To this end, various external field effects have been investigated to modify the suspension microstructure without manipulating the ceramic particles directly. In a previous work in the field of ice templating it has been shown that AC electric fields are able to produce microstructural changes in ice templated ceramics that have significantly improved the final mechanical properties. However, the mechanisms for this process are still not well understood in ceramics.

To …

Development And Characterization Of Forcespinning® Mesquite Gum Nanofibers, Cristobal Rodriguez, Victoria Padilla, Karen Lozano, Alexa Villarreal, Luis A. Materon, Robert Gilkerson

Mechanical Engineering Faculty Publications

In this study, nanofibers incorporating Prosopis glandulosa mesquite gum (MG) exudate combined with biodegradable polymers, pullulan (PL) and chitosan (CH), were produced via the Forcespinning® technique. The nonwoven composite membranes were characterized via scanning electron microscopy followed by thermogravimetric and Fourier-transform infrared spectroscopy analysis. MG nanofiber composites comprised long, continuous fibers with an average fiber diameter of 523 ± 180 nm and 760 ± 225 nm for 18.1 and 28 wt% of MG, respectively. These composite membranes were water-stable after crosslinking via heat treatment with a ∼3 % water absorption capacity, and demonstrated a thermal capability with an increasing …

Experimental Tests And Numerical Study Of Trajectories Of Different Types Of Dropped Objects, Yi Li

LSU New Orleans Theses and Dissertations

In marine and offshore engineering, dropped objects, such as drill pipes, anchor chains, containers and some small parts, can accidentally fall into the water from ships or offshore platforms, causing casualties on deck or damage to underwater equipment. Damaged equipment can further harm the environment, such as oil spills from damaged wellheads. Therefore, for safe engineering and environmental protection reasons, we need to develop methods and tools that can predict the trajectory of dropped objects.

In this dissertation, we first study containers dropped from ships. More and more containers are falling into the sea due to bad weather. Containers lost …

Dendrimer-Based Drug Delivery Systems: History, Challenges, And Latest Developments, Juan Wang, Boxuan Li, Li Qiu, Xin Qiao, Hu Yang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Since the first dendrimer was reported in 1978 by Fritz Vögtle, dendrimer research has grown exponentially, from synthesis to application in the past four decades. The distinct structure characteristics of dendrimers include nanoscopic size, multi-functionalized surface, high branching, cavernous interior, and so on, making dendrimers themselves ideal drug delivery vehicles. This mini review article provides a brief overview of dendrimer's history and properties and the latest developments of dendrimers as drug delivery systems. This review focuses on the latest progress in the applications of dendrimers as drug and gene carriers, including 1) active drug release strategies to dissociate drug/gene from …

A Pipeline To Generate Deep Learning Surrogates Of Genome-Scale Metabolic Models, Achilles Rasquinha

School of Computing: Dissertations, Theses, and Student Research

Genome-Scale Metabolic Models (GEMMs) are powerful reconstructions of biological systems that help metabolic engineers understand and predict growth conditions subjected to various environmental factors around the cellular metabolism of an organism in observation, purely in silico. Applications of metabolic engineering range from perturbation analysis and drug-target discovery to predicting growth rates of biotechnologically important metabolites and reaction objectives within dierent single-cell and multi-cellular organism types. GEMMs use mathematical frameworks for quantitative estimations of flux distributions within metabolic networks. The reasons behind why an organism activates, stuns, or fluctuates between alternative pathways for growth and survival, however, remain relatively unknown. GEMMs …

Backpack Effects On Two-Dimensional Gait Spatiotemporal And Kinematic Parameters, Nardo Rizaldy, Alvin Alvin, Wirawan Lingga, Ethan B.W. Goeij, F. Ferryanto

Journal of Mechanical Engineering Science and Technology (JMEST)

Loads could affect the body gait in various ways. Backpacks, sling bags, suitcases, and even trolleys could hugely affect human gait without us realizing it. The effects of these loads have been scientifically researched in biomechanics and sports science for the past few years. For instance, the comparison of walking with and without a backpack could easily reveal significant differences in body segments, which could be utilized for therapy and medicine development. The aim of this research is to determine the differences of the spatiotemporal kinematic parameters between a conventional human gait and a backpackloaded gait. Some parameters to be …

Application Of Uas‑Based Remote Sensing In Estimating Winter Wheat Phenotypic Traits And Yield During The Growing Season, Kianoosh Hassani, Hamed Gholizadeh, Saleh Taghvaeian, Victoria Natalie, Jonathan Carpenter, Jamey Jacob

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Phenotyping approaches have been considered as a vital component in crop breeding programs to improve crops and develop new high-yielding cultivars. However, traditional field-based monitoring methods are expensive, invasive, and time-intensive. Moreover, data collected using satellite and airborne platforms are either costly or limited by their spatial and temporal resolution. Here, we investigated whether low-cost unmanned/unoccupied aerial systems (UASs) data can be used to estimate winter wheat (Triticum aestivum L.) nitrogen (N) content, structural traits including plant height, fresh and dry biomass, and leaf area index (LAI) as well as yield during different winter wheat growing stages. To achieve …

Key Pretreatment Technologies For Coalbed Gas Bioengineering And Review On Their Mechanism Of Action, Bao Yuan, Chang Jianing, Liu Xiangrong, Xia Daping, Wang Yaya

Coal Geology & Exploration

Coalbed gas bioengineering (CGB) is a new technology for the purpose of realizing the clean utilization of coal resources and the enhanced recovery of coalbed gas. To explore the key characteristics of the pretreatment technologies of CGB, hydrocarbon generation potential and its mechanism of action, conclusion and summary was made for various pretreatment technologies herein. Meanwhile, the pretreatment technologies were divided into three types according to the action mode of coal (organic matter) and bacteria (microorganism): microflora optimization and improvement, coal dissolution and oxidation, and biological stimulation and synergy. By comparing the capability of coal to generate methane through microbial …

Frequency Domain Diffuse Optics Spectroscopies For Quantitative Measurement Of Tissue Optical Properties, Sadhu Moka

USF Tampa Graduate Theses and Dissertations

Tissue oxygen saturation, blood flow and blood volume are physiological bio-markers of tissue health. Diffuse Optical Spectroscopy(DOS) and Diffuse Correlation Spectroscopy (DCS) are two complementary approaches to measure tissue oxygen saturation and blood flow respectively. Quantitative Diffuse Optical Spectroscopy (DOS) uses multi-spectral intensities of near-infrared light that have been modulated at RF frequencies to estimate static tissue optical properties and hence concentrations of oxygenated and de-oxygenated hemoglobin. Diffuse Correlation Spectroscopy estimates tissue dynamics - i.e., blood flow, by measuring temporal intensity auto-correlation function of backscattered light diffusing through the tissue. Conventionally, DCS instruments use coherent light sources with constant intensity. …

Bioactive Self-Forming Hydrogels For Biomedical Applications, Kirstene Arcuino Gultian Giddings

Theses and Dissertations

Hydrogels are soft biomaterials that feature a wide range of physical and biochemical properties. Although highly versatile, hydrogels typically require an exogeneous input (e.g., light, pH, temperature) to form, and this limits their use to conditions where a catalyst is present. The goal of this dissertation is to expand the use of catalyst-based hydrogels by developing hydrogels with independently tunable properties which gel in situ without external stimuli. This new class of hydrogels was developed by first modifying macromers with norbornene (Nor) or tetrazine (Tet) moieties. Macromers containing Nor or Tet remain liquid when dissolved, and upon mixing self-form into …

Formation Mechanism Of Coalbed Methane In Dafosi Mine Field, Huanglong Coalfield, Liu Kaide, Yao Kaiwen, Chen Nengyuan, Fan Zhangqun, Li Shujia, Zheng Han, Yue Wenping, Li Xiaolong

Coal Geology & Exploration

Dafosi mine field is a typical low-rank coalbed methane (CBM) field in Binchang mining area of Huanglong Jurassic. There are many coalbed methane wells in the field, but few researches are performed on the formation mechanism of coalbed methane. Thus, it is of great guiding significance to clarify the geochemical characteristics and formation mechanism of coalbed methane (CBM) in the mine field, which could provide important basis for the analysis on productivity difference of high- and low-yield CBM Wells. For this reason, the samples of drained gas at the wellhead of six CBM wells, 22 coal samples of No.4 coal …

Neroimaging Of Brain Activaion Using Diffuse Optical Tomography, Jingyu Huang

USF Tampa Graduate Theses and Dissertations

This research has two parts. The first part focuses on the use of non-invasive imaging technique, diffuse optical tomography (DOT), to study the brain activation during the stimulation in the clinical room. It further extends the application of DOT by using it to monitor the hemodynamic response during the TMS stimulation in different parameters. Diffuse optical tomography (DOT) is based on NIR light that exploits the relative transparency of biological tissue. The part two and three extends the application in the hospital for delirium patient study and arm muscle dystrophy by adding the sources and detectors to monitor the brain …

Biochar Amended Biological Systems For Enhanced Landfill Leachate And Lignocellulosic Banana Waste Treatment, Xia Yang

USF Tampa Graduate Theses and Dissertations

Biochar is an inexpensive and environmentally friendly carbonaceous pyrolysis byproduct with a high surface area, pore volume, and adsorption capacities for inorganic and organic compounds. The goal of this dissertation is to evaluate the feasibility of biochar application in biological treatment systems for enhanced waste management. Three major objectives guided this research to provide a compressive understanding of biochar enhancement effects on biological treatment systems for contaminant removal, energy recovery, and environmental impacts as well as essential factors influencing biochar production and properties.

In Objective 1 a low-cost hybrid Constructed Wetland (CW) system modified with biochar/zeolite was developed for enhanced …

Influence Of Salts On The Photocatalytic Degradation Of Formic Acid In Wastewater, Azzah Nazihah Che Abdul Rahim, Shotaro Yamada, Haruki Bonkohara, Tsuyoshi Imai, Yung-Tse Hung, Izumi Kumakiri

Civil and Environmental Engineering Faculty Publications

Conventional wastewater treatment technologies have difficulties in feasibly removing persistent organics. The photocatalytic oxidation of these contaminants offers an economical and environmentally friendly solution. In this study, TiO2 membranes and Ag/TiO2 membranes were prepared and used for the decomposition of dissolved formic acid in wastewater. The photochemical deposition of silver on a TiO2 membrane improved the decomposition rate. The rate doubled by depositing ca. 2.5 mg of Ag per 1 g of TiO2. The influence of salinity on formic acid decomposition was studied. The presence of inorganic salts reduced the treatment performance of the TiO2 membranes to half. Ag/TiO2 membranes …

A Real-Time Ultrasound Simulation Platform Using Ray Tracing And Its Integration With Virtual Reality, Bo Peng, Qiang Wang, Ruibing Qing, Lixue Yin, Jingfeng Jiang

Journal of System Simulation

Abstract: In order to further improve the efficacy of ultrasound training and reduce the cost. An ultrasound training system that is integrated with a VR environment is developed. The main contribution of this study is to incorporate the Ray-tracing based ultrasound image simulation approach into a virtual reality environment, taking advantage of immersive VR experience for medical ultrasound training. The simulated ultrasound images obtained by the proposed method are then compared to images that are simulated using a generative adversarial network (GAN) technique and Field II ultrasound simulator. The data show that the ultrasound simulator can produce high-quality simulated …

Transcriptomic Analysis Of A 3d Blood-Brain Barrier Model Exposed To Disturbed Fluid Flow., Nesrine Bouhrira, Brandon J Deore, Kiet A Tran, Peter Galie

Henry M. Rowan College of Engineering Departmental Research

Cerebral aneurysms are more likely to form at bifurcations in the vasculature, where disturbed fluid is prevalent due to flow separation at sufficiently high Reynolds numbers. While previous studies have demonstrated that altered shear stress exerted by disturbed flow disrupts endothelial tight junctions, less is known about how these flow regimes alter gene expression in endothelial cells lining the blood-brain barrier. Specifically, the effect of disturbed flow on expression of genes associated with cell-cell and cell-matrix interaction, which likely mediate aneurysm formation, remains unclear. RNA sequencing of immortalized cerebral endothelial cells isolated from the lumen of a 3D blood-brain barrier …

Instructional Systems Design And The Diffusion And Adoption Of Technology: (Volume 1), Miguel Ramlatchan (Author & Editor), Mark Parsons (Author), Meghan Soldani (Author), Josie Joswick Mendoza (Author), Maria Satre (Author), Brittany Spitz (Author), Jasmine Bundy (Author), Amanda Kline (Author)

Distance Learning Faculty & Staff Books

Instructional designers, instructional systems designers, and other educational technologists are, by their nature, innovators. These professionals apply and extend the applied science of learning, systems, communication, and instructional design theory to help students learn. Technology in some capacity is used to make the connections between subject matter experts, teachers, instructors, and their learners. It is common for instructional designers to seek new tools, techniques, and innovations for the improvement of learning, access, quality, and student satisfaction. However, the adoption and diffusion of new educational technology and innovation is a complex process that depends on many variables. Understanding these processes and …

In Vitro Models For The Study Of Liver Biology And Diseases: Advances And Limitations, Savneet Kaur, Srivatsan Kidambi, Martí Ortega-Ribera, Le Thi Thanh Thuy, Natalia Nieto, Victoria C. Cogger, Wei-Fen Xie, Frank Tacke, Jordi Gracia-Sancho

Department of Chemical and Biomolecular Engineering: Faculty Publications

In vitro models of liver (patho)physiology, new technologies, and experimental approaches are progressing rapidly. Based on cell lines, induced pluripotent stem cells or primary cells derived from mouse or human liver as well as whole tissue (slices), such in vitro single- and multicellular models, including complex microfluidic organ-on-a-chip systems, provide tools to functionally understand mechanisms of liver health and disease. The International Society of Hepatic Sinusoidal Research (ISHSR) commissioned this working group to review the currently available in vitro liver models and describe the advantages and disadvantages of each in the context of evaluating their use for the study of …

Exosomes Derived From Differentiated Human Admsc With The Schwann Cell Phenotype Modulate Peripheral Nerve-Related Cellular Functions, Bo Liu, Yunfan Kong, Wen Shi, Mitchell Kuss, Ke Liao, Guoku Hu, Peng Xiao, Jagadesan Sankarasubramanian, Chittibabu Guda, Xinglong Wang, Yuguo Lei, Bin Duan

Department of Mechanical and Materials Engineering: Faculty Publications

Peripheral nerve regeneration remains a significant clinical challenge due to the unsatisfactory functional recovery and public health burden. Exosomes, especially those derived from mesenchymal stem cells (MSCs), are promising as potential cell-free therapeutics and gene therapy vehicles for promoting neural regeneration. In this study, we reported the differentiation of human adipose derived MSCs (hADMSCs) towards the Schwann cell (SC) phenotype (hADMSC-SCs) and then isolated exosomes from hADMSCs with and without differentiation (i.e., dExo vs uExo). We assessed and compared the effects of uExo and dExo on antioxidative, angiogenic, antiinflammatory, and axon growth promoting properties by using various peripheral nerve-related cells. …

Spacecraft Systems & Navigation, Christopher Vanacore

Student Works

This textbook is steered towards higher educational course entailed in Commercial Space Operations. This textbook will be covering in detail Orbital Satellites, and Spacecraft. These topics are discussed according to their application, design, and environment. The power system, shielding and communication systems are reviewed along with their missions, space, environment and limitations. Any vehicle, whether manned or unmanned, intended for space travel is a spacecraft. A spacecraft's required systems and equipment depend on the information it will acquire and the tasks it will perform. Although their levels of sophistication vary widely, they re all subject to the harsh conditions of …

Aldosterone Treatment Protects Connexin 30 And 43 Expression For Age-Related Hearing Loss, Jennifer A. Pineros Valencia

USF Tampa Graduate Theses and Dissertations

Age-related hearing loss (ARHL), also known as presbycusis, is the number one communication disorder affecting our aged population. Connexin proteins are essential for intercellular communication throughout the human body. Mutations in connexin genes have been linked to human syndromic and nonsyndromic deafness; thus, we hypothesize changes in connexin gene and protein expression with age may be involved in the development of ARHL. In our current study, connexin mRNA gene expression for CBA/CaJ mice at different age points were examined and correlations were analyzed between the changes in gene expression and functional hearing measures, such as ABRs and DPOAEs. Moreover, we …

Applying Biomimetic Passive Dynamics To A Quadruped Robot Leg, Emma Krnacik

Dissertations and Theses

The study of synthetic nervous systems is an emerging field within biomimetic robotics as an alternative to more classic control techniques. As the modeling of these nervous systems becomes more accurate, it is important to note that the nervous system and physical system co-evolved and continue to operate in an interdependent fashion. Many legged robots, including the existing quadruped in the AARL, have leg systems that may have similar geometrical properties to that of a mammal, but have significantly different dynamic properties. This paper presents a method for designing a limb so that the passive dynamics more accurately represent that …

Space Science In Manned Space Flight, Deep Space Exploration And Scientific Satellite Programs, Ji Wu

Bulletin of Chinese Academy of Sciences (Chinese Version)

In order to implement President Xi's instruction on promoting space science, space technology, and space application all together, national space programs have been developed fast, which are witnessed recently. Space science has become the hot research topic for more and more universities and research institutions. Nevertheless, there are still questions and puzzles about how could space science play its role in manned spaceflight, deep space exploration, and scientific satellites. This paper discusses the role of space science in all three kinds of space programs, starting from the history of space science, and the characteristics of manned space flight, deep space …

Effectiveness Of Clay Nanotube Blended Coating Materials For Thermal Insulation, Hawa Hashm

Doctoral Dissertations

Studies conducted by the U.S. Department of Energy reported that heating and cooling systems use nearly 60% of the total energy consumed in a building, while approximately 31% of that energy loss occurs through the improperly insulated floor, walls, and ceiling. Hot summers or severely cold weather can make these problems worse. The passing of conditioned air through these building materials is a substantial source of energy loss, which has driven significant investigation into new environmentally friendly, sustainable, and cost-effective solutions. The main objective of the research was to experimentally evaluate the thermal conductivity of paints blended with halloysite nanotubes …

Lewis-Base Thioacetamide Assisted Crystallization Of Lead-Free Perovskite Solar Cells For Improved Efficiency, Raja Sekhar Bobba

Dissertations - ALL

High-efficiency perovskite solar cells that are also very cheap to produce have been rapidly developed in response to the growing global demand for electricity. However, the light absorber materials used in cutting-edge perovskite solar cells include lead, which has been linked to health risks for people and other living organisms. Accordingly, the developing front in photovoltaic research is the discovery and development of new lead-free perovskite materials for the future global commercialization of non-toxic, stable, and efficient perovskite solar cells, by replacing hazardous lead with non-toxic metal elements in the same group as lead in the periodic table, lead-free PSCs …

A Patient-Specific Algorithm For Lung Segmentation In Chest Radiographs, Manawaduge Supun De Silva, Barath Narayanan Narayanan, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

Lung segmentation plays an important role in computer-aided detection and diagnosis using chest radiographs (CRs). Currently, the U-Net and DeepLabv3+ convolutional neural network architectures are widely used to perform CR lung segmentation. To boost performance, ensemble methods are often used, whereby probability map outputs from several networks operating on the same input image are averaged. However, not all networks perform adequately for any specific patient image, even if the average network performance is good. To address this, we present a novel multi-network ensemble method that employs a selector network. The selector network evaluates the segmentation outputs from several networks; on …

Biomass Characterization And Insulation Optimization Studies, Hussein Awad Kurdi Saad

Doctoral Dissertations and Master's Theses

This study indicates how biomass materials can be effectively used as naturally sustainable alternatives to insulation materials. Barley grains and oak leaves, straw, and jute are collected, and crushed into powders/ chopped pieces. The physical characteristics are measured to characterize each powder. The biomass powder reinforced composites are manufactured in varying weight ratios. The density and thermal conductivity of composite materials are measured. The properties of composites compared to those of commercial insulation materials are found to be close to them. Furthermore, genetic algorithms (GA) can be used to achieve multi-objective optimization entailing maximizing insulation (minimizing heat transfer) and simultaneously …

Genetic Code Expansion In Pseudomonas Putida Kt2440, Xinyuan He, Tian Gao, Yan Chen, Kun Liu, Jiantao Guo, Wei Niu

Department of Chemical and Biomolecular Engineering: Faculty Publications

Pseudomonas putida KT2440 is an emerging microbial chassis for bio-based chemical production from renewable feedstocks and environmental bioremediation. However, tools for studying, engineering, and modulating protein complexes and biosynthetic enzymes in this organism are largely underdeveloped. Genetic code expansion for the incorporation of unnatural amino acids (unAAs) into proteins can advance such efforts and, furthermore, enable additional controls of biological processes of the strain. In this work, we established the orthogonality of two widely used archaeal tRNA synthetase and tRNA pairs in KT2440. Following the optimization of decoding systems, four unAAs were incorporated into proteins in response to a UAG …